Developing device for processing copying materials



y 1970 w. LIMBERGER ET AL 3,509,809

DEVELOPING DEVICE FOR PROCESSING COPYING MATERIALS Filed May 12, 196'? 4 Sheets-Sheet 1 y 5, 1970 w. LlMBE-RGER ET AL 3,509,809

DEVELOPING DEVICE FOR PROCESSING COPYING MATERIALS 4 Sheets-Sheet 2 Filed May 12. 196'? y 1970 w. LIMBERGER ET AL 3,509,809

DEVELOPING DEVICE FOR PROCESSING COPYING MATERIALS Filed May 12, 1967 4 Sheets-Sheet 5 Fly. 3

May 5, 1970 w. LIMBERGER ET AL 3,509,809

DEVELOPING DEVICE FOR PROCESSING COPYING MATERIALS Filed May 12, 1967 4 Sheets-Sheet 4 Fly. 4

Fig 5 Fig. 6 46 46 57 a K v United States Patent M US. Cl. 95-94 14 Claims ABSTRACT OF THE DISCLOSURE An apparatus for developing copying materials using the silver salt diffusion method, wherein the exposed negative is treated with a developer and the positive or receiving material is treated with another liquid. The negative and positive materials are guided through separate treating tanks and thereafter brought into engagement with each other by a pair of squeeze and transport rollers at the exit ends of the tanks. The treating tank for the positive or receiving material has a surface wetting device for applying the liquid to the material, and a pair of squeeze rollers for removing any excess treating liquid from the positive material before it is brought into engagement with the negative material by the squeeze and transport rollers.

Description The invention relates, as indicated, to a developing apparatus for processing copying materials, using the silver salt diifusion method, wherein the exposed negative material is wetted with a developing fluid and the positive or receiving material is subjected to a surface treatment by means of another liquid, and wherein there are provided a common pair or squeeze and transport rollers for both materials and a surface wetting device for the said receiving material.

It has already been proposed to provide a separate pair of press rollers for a web of receiving material. However, this web passes through a liquid bath, and only insufficient expulsion of the quite substantial quantities of liquid could be achieved. According to another proposal, a surface wetting roller has been associated directly with a contact pressure roller, with the object of removing simultaneously excess liquid from the receiving material during the application of the liquid. Here, it has become apparent that, although the two processes of applying the surface wetting agent and the squeezing out of the excess liquid in one and the same process offers substantial advantages, the intensity of these two processes may be substantially improved.

The present invention has the object of improving the proposed devices and of providing apparatus not only for applying the liquid but also for working it into the surface of the receiving material, whilst simultaneously providing a sufficient squeezing out of the excess liquid.

According to the invention, a negative material is used which has a halide silver emulsion layer, on which a picture has been exposed, which is transferred after development, by diffusion, to the receiving material.

German Pat. No. 764,572 describes the so-called silver salt diffusion method, wherein widely different substances are used as receptors, such as unlayered'paper, textiles, Wood, Celluloid, other synthetic resins, and the like. In this connection it should be mentioned that the term material used in this description, comprises foliate material.

According to the mentioned German Patent, the

3,509,809 Patented May 5, 1970 transfer may be supported by the presence of substances furthering the diffusion. The diffusing or diffused silver halide may be developed in a picture without exposure, wherein this development is supported by the addition of nuclei or reacting substances. The developed picture is applied, for example, to a baryte paper or a textile base, wetted in the same bath as the silver halide material.

In the practical embodiment of the method such as it has been developed for commercial uses with foliate copying materials, a separate positive or receiving layer has always been provided, which contains the reduction nuclei. Usually this layer is arranged on a special carrier so that layer and carrier form the receptor material.

If the invention uses two different liquids, particularly the liquid for the receiving material will be a so-called germinating bath, imparting to the receiving material the property of responding even in the unlayered condition to the effects of the developed negative material, with regard to the distribution of the picture.

Although it is well known to treat the negative material and the receiving material in different baths, wherein the guides for different baths may be internested, the present invention has the object of providing a special effect with regard to the provision of the wetting liquid for the receiving material, more particularly in conjunction with a surface wetting of the receiving material.

According to the invention, this object is realized in that an additional squeezing out device is arranged between the surface wetting device and the common pair of squeeze and transport rollers in the guide for the receiving material.

The invention is based on the knowledge that the pressing in, and possibly even only the penetration, is of particular importance, before excess liquid is expelled. The object is here to saturate with the liquid provided for this material at least a layer or a surface zone of the receiving material to a certain depth.

Compared with the known constructions, the working stages of applying the wetting liquid to the receiving material and of the squeezing out, before the receiving material is combined with the negative material, are solved in a particularly advantageous manner. By separating the surface wetting and the additional squeezing successively in the guide for the receiving material, the invention creates a time constant as a function of the travelling speed, giving the applied wetting liquid an opportunity to settle in the surface of the receiving material or to be distributed therein, before it reaches the squeezer.

The squeezing device may comprise belts running one on the other and along surfaces, rollers running along surfaces, or the like. In a preferred embodiment of the invention, the squeezing device consists of a pair of driven squeeze rollers. With these means the effect is particularly good because the conact pressure is applied always to a short section of the materials, with a kind of milling effect, because the sections adjacent to the linearly compressed sections can expand, owing to the displacement of material, and absorb more liquid on this condition. Especially in the section downstream of the pair of squeeze rollers, this results in the surface layer of the material being saturated with the remaining liquid, producing a quasi-dry state in which, however, the surface layer inside the material is perfectly well saturated with the wetting agent or solution.

Preferably, the surface wetting device is a conventional surface wetting roller, the peripheral speed of which is synchronized with that of the additional pair of squeeze rollers. The one-sided application of the wetting liquid produces a favourable treatment of the receivin g material.

In a particularly preferred embodiment, the surface wetting roller is associated with a contact pressure device, such as, for example, at least on pressure roller, effecting a preliminary compression with a view to working in the applied liquid, and the periphery of the pressure device and/or surface wetting roller is provided with profiles for introducing the liquid into the range of the contact zone, whilst the additional pair of squeeze rollers has a substantially smooth surface. This arrangement has the advantage that the liquid is practically rolled in, because the profiles, which may be dish-shaped, for example, prevent the liquid escaping from the contact zone, and because these dish-shaped profiles retain even in the zone of maximum pressure a certain amount of liquid which can enter into the material. On the other hand, the smooth construction of the squeeze rollers through which the material passes after a certain lapse of time ensures the removal of any liquid actually present on the surface of the receiving material.

Preferably, the contact pressure roller and the roller of the additional pair of squeeze rollers are adapted to be moved towards the associated counter-roller, such as known in the art, and springs are provided for generating the contact pressure.

According to another feature of the invention, a plurality of contact rollers are arranged around a section of the periphery of the surface wetting roller. According to another embodiment, the contact pressure device consists of an endless belt passing over a section of the surface of the surface wetting roller. These means can be used at choice.

According to yet another feature of the invention, a guide element extends transversely across the path of the receiving material upstream of the surface wetting roller, in order to guide this material to the surface of the roller. Such arrangements are known in the art in other connections.

Preferably, the additional pair of squeeze rollers is arranged within the vertical projection of a special trough for the treatment liquid for the receiving material. This has the object of preventing mixing of the liquids serving for treating the receiving material and the negative material.

The invention will be further described, by way of example, with reference to the accompanying drawing showing the essential parts of embodiments thereof, and in which:

FIG. 1 is a side elevation of a device, with the front side of the main container removed, showing in partial cross-section the inner elements of the device;

FIG. 2 is a view corresponding to that of FIG. 1, of an additional contact pressure roller;

FIG. 3 is a cross-section along the line IIIIII in FIG. 2;

FIG. 4 is a cross-section along the line IVIV in FIG. 2;

FIG. 5 shows a partial side elevation of a modification, in which equivalent parts are designated by the same reference numerals with an apostrophe and FIG. 6 is a partial side elevation of a further modification of FIG. 2.

Description of the preferred embodiments The device shown has an outer trough 1 with a bottom 2, two parallel side walls, of which the rearward wall is shown at 3, and end walls 4 and 5. This vessel contains a liquid, the level of which is shown at 6. Into the liquid leads a guide 7, formed by a plate, and more particularly an arcuate, profiled, corrugated or perforated plate, or by webs which may extend parallel or obliquely to the direction of advance of the material. This guide 7 extends into the lowest part of the vessel 1. This element is associated with another guide element 8, facing upwardly, and which may have the same construction as the first element. It terminates near the point of contact between the rollers 30 and 31 of a so-called common pair of squeeze and transport rollers.

Suspended in the outer trough 1 is an inner trough 11, having a downwardly closed bottom. The trough 11 may be supported in the vessel 1, for example, by a support 12, and by means of lugs 51, 52, shown in FIG. 3, resting on the side walls 53, 54 of the trough 1. It may be seen that the trough has on the inlet side above the guide 7 a guide-like extension 13, the section of which, extending beyond the side wall 3, may have support lugs.

The trough 11 contains a second liquid, a so-called germinating bath, the level of which is shown at 14.

A surface wetting roller 15 is rotatably mounted within the trough 11. The mounting will be described in detail further below. The top section 16 of the surface wetting roller is located substantially at the level of the top 17 of the guide-like extension, extending between the side walls 18 of the trough 11 and terminating in front of the roller 15. The top may be formed, for example, by webs of foil-like, vertically positioned strips, one of which has an end 19, and arranged side by side. Guiding along webs has the advantage that the surface of the material sliding thereover is protected. The upper side 17 terminates substantially at the same level as the top of the wetting roller 15.

In order to produce a mechanically favourable construction, the rear end wall 5 carries a supporting mechanism, having brackets extending parallel to the side walls of the trough 1 and, by means of a step, also parallel to the side walls of the trough 11, and always extending inwardly along the side walls; one of these brackets is shown at 20. The step, extending substantially along the dotted line 21, has the object of bridging the inwardly directed projection between the inside of the side walls of the trough 1 and the inside of the side walls of the trough 11. If the bottom surface 22 of the trough 11 is mounted in a liquid-tight way directly on the side walls of the trough 1, this step is unnecessary.

At their ends, the brackets 20 have at one end a connecting wall portion 23, extending parallel to the rearward end wall 5 and resting on webs 24 of this end wall 5. At the upper end is a clamp 25 overlying the end Wall, and engaging on the outside of the end wall under a rim 26. The brackets form arms 55, 56 (FIG. 3), having a first leg 27, followed by a downwardly directed step 28, and a second leg 29, extending substantially parallel to the leg 27. The rollers 30, 31 of a common pair of squeeze and transport rollers are mounted in the leg 27 These r011- ers are resiliently urged one against the other; means to this end are known in the art and do not form part of the invention. FIG. 4 shows the mounting means 57, 58 for the forward roller 30. These means are adapted to be displaced relative to the mounting means for the roller 31, and a spring may be arranged between the individual mounting means, such as shown, by way of example, in FIG. 4 for the rollers 34, 35. The rollers are driven in the sense indicated by the arrows 32, 33. In the step or web 28, a pair of squeeze rollers 34, are located. With regard to the connecting line between the axes of the rollers, these rollers are substantially perpendicular to the common squeeze and transport roller pair 30, 31. Also these rollers 34, 35 are urged towards each other and have preferably a smooth surface.

The mounting means for the rollers 34, 35 are shown at 59, 60, 61 and 62. These have vertical side faces and are guided in slots 63, 64 of the arms 55, 56. The shafts ends 65, 66, 67 and 68 carry abutments 69, 70, 71, 72 for springs 73, 74, which pull the top roller 34 towards the bottom roller 35.

The leg 29, and the two legs on the arms 55, 56, repectively, arranged on both sides of the support, have hookshaped bearings 36, into which are fitted the stub axles 37 of the wetting roller 15. The wetting roller 15 has on one end face a step-shaped projection 38, or a correspondingly mounted disk, which collaborates with a projection 39 or a disk on the squeeze roller 35. The projections or disks are interconnected by a cable or belt 40.

The pair of squeeze rollers 34, 35 is driven as indicated by the arrows 41, 42 so that also the wetting roller revolves in the direction of the arrows 43.

The top of the wetting roller 15 is above the liquid level 14 so that material applied via the top 17 of the guide elements runs over the section 16 and is thereby wetted. The leg 29 of the bracket has at its outer end a slot 44, into which is fitted an angled guide member 45, for example, of synthetic resin, which extends transversely over the guide path of the receiving material. The guide element has the object of urging the receiving material from the top on to the upper section of the wetting roller 15, or of guiding it thereto, in order to ensure complete wetting. As may be seen, the guide member is exchangeable in order to enable the use of different designs and different downwardly directed profiles, and thus to change the intensity of the wetting by the roller 15.

According to a preferred embodiment, shown in FIG. 2, the surface wetting roller 15 co-operates with a contact pressure roller 46, guided vertically movably in the side walls 3 of the trough 1, as shown in FIG. 3, and affected by the pressure of springs 75, 76, which urge it towards the wetting roller 15. The bearing means are shown at 77, 78. The springs, pressing the pairs of rollers together, such as on the bearings 30, 34, 46, are known in the art. of importance is the coordination of the direction of the pairs of rollers as hereinbefore described.

The device shown has the advantage that the driving members may be easily dismantled, enabling the whole device to be easily disassembled.

With regard to the driving member 40, it may be said that a motor 47 is arranged on the squeeze roller 34, such as via a coupling 79. A corresponding motor 48 may be arranged on the shaft of the common squeeze and transport roller 30, and in special embodiments, the different speeds of these motors 47 and 48 may cause the peripheral speed of the rollers 30 and 31 to be greater than that of of the rollers 34, 35. According to FIG. 4, the drive motor 47 for the squeeze roller 34 is mounted on a bracket 80 on a frame 81.

Naturally, only a single drive motor need be provided, and the driven element may be connected by a cable or belt drive with the other pair of rollers, similar to the system 40. If the common squeeze and transport roller pair is to run faster, a transmission may be interposed. During operation, the receiving material, which is preferably in sheet form, is applied as shown by the arrow 49 and travels along this arrow over the top 17, the upper section of the wetting roller 15 and through the pair of squeeze rollers 34, 35 to the common pair of squeeze and transport rollers 30 and 31. The negative material is applied along the twin-headed arrow 50 and passes over the guide elements 7 and 8 to the common squeeze and transport rollers 30, 31.

It is essential for the invention that the trough 11 and the parts cooperating therewith, such as the surface wetting roller 15, its stub axles 37, the legs of the bracket 20 and the parts arranged thereon, for example, the squeeze rollers 34, 35, at least insofar as they are located within the zone of the trough 11, as well as the contact pressure roller 46 and the guide element should be free from metallic surfaces. In this way it can be prevented that the germinating bath in the trough 11 is destroyed with time by some catalysis. Hence, preferably all elements so arranged -are made of synthetic resins. Where such elements, such as, for example, rollers, axles or shafts, are made of metal, they are provided with a plastic coating acting as screen. More particularly, also the driving means are made of plastics.

In FIG. 3, the side walls 81, 82 are shown with projections 83, 84, which rest on the lugs 51, 52.

It may be seen from FIGURE 5 that the surfaces wetting roller 15 has, on its upper side in addition to the contact pressure roller 46, two further contact pressure rollers 46' and 46", slightly offset peripherally; these rollers are mounted near each other along the upper section of the surface wetting roller 15 in the same way, as shown in FIG. 3 for the roller 46.

According to FIG. 6, a surface wetting roller 15' is mounted in the same way as the surface wetting roller 15 in FIG. 1. Corresponding to the mounting for the contact pressure roller 46, there are two guide rollers 85, 86,

- whose axes are parallel to the axis 37' of the surface wetting roller 15, and over which and endless belt 87 is so guided that through the guide elements 17, 19 receiving material is applied between the belt 87 and the surface wetting roller 15'.

We claim:

1. A device for developing copying materials using the silver salt dififusion method and a negative and a receiving material, to which latter the picture exposed on the negative material is transferred, the said device comprising a first vessel with a developing liquid for the negative material, first guide elements on said first vessel for guiding the negative material through said developing liquid, a second vessel with a second liquid for treating the receiving material, second guide elements for guiding the receiving material to and through said second vessel, a pair of squeeze and transport rollers in front of which said first and second guide elements terminate in order to pass the negative material and the receiving material, after separate wetting by their respective liquids, in superimposed relationship through said pair of squeeze and transport rollers, and additional squeeze means engaging the receiving material within the zone of said second guide elements and between the second treatment liquid and said pair of squeeze and transport rollers.

2. A device as set forth in claim 1, wherein the second guide elements extend over the supply of treatment liquid in said second vessel, and wherein a device is provided for applying the liquid from the second vessel to the receiving material passing through the second guide elements.

3. A device as set forth in claim 1, wherein said additional squeeze means comprises a first and a second roller both of which are mounted rotatably relative to both vessels, and means positively driving at least one of said first and second rollers, bearing means for said first and second rollers, said bearing means for both first and second rollers being so spaced that said first and second rollers run on each other under contact pressure.

4. A device as set forth in claim 3 wherein said device for applying the second liquid comprises a surface wetting roller, drive means interconnecting said surface wetting roller and one of said first and second squeeze rollers to synchronize the peripheral speed of said surface wetting roller with that of said first and second squeeze rollers.

5. A device as set forth in claim 4, wherein said second vessel, said surface wetting rollers the bearing means for said squeeze rollers and the squeeze rollers have nonmetallic surfaces.

6. A device as set forth in claim 3, wherein said second treatment liquid is arranged in said second vessel, and comprising the said additional pair of squeeze rollers (34, 35) above said second vessel, in a position to guide the pressed-out liquid into said second vessel.

7. A device for developing copying materials using the silver salt diffusion method and a negative and a receiving material, to which latter the picture exposed on the negative material is transferred, the said device comprising a first vessel with a developing liquid for the nega tive material, first guide elements on said first vessel for guiding the negative material through said developing liquid, a second vessel with a second liquid for treating the receiving material, second guide elements for guiding the receiving material to and through said second vessel, a pair of squeeze and transport rollers, in front of which said first and second guide elements terminate in order to pass the negative material and the receiving material, after separate wetting by their respective liquids, in superimposed relationship through said pair of squeeze and transport rollers, and additional squeeze means engaging the receiving material within the zone of said second guide elements and between the second treatment liquid and said pair of squeeze and transport rollers; a device for applying the liquid from said second vessel to the receiving material passing through the second guide element, said device for applying the second liquid comprising a surface weting roller with end faces and stub axles, bearing means for said stub axles arranged in fixed relation relative to said second vessel so as to locate said surface wetting roller rotatably at a level in which its lower section is submerged in said second treatment liquid with its upper section extending to the plane formed by the said second guide elements, said second guide elements terminating in front of and substantially at the level of the upper section of said surface wetting roller, and means positively driving said surface wetting roller, and means positively driving said surface wetting roller.

8. A device as set forth in claim 7 wherein said additional squeeze means comprises cooperating squeeze rollers, and comprising additional bearing means, wherein at least one additional contact pressure roller is mounted in these bearing means, and the last mentioned bearing means being so arranged that the contact pressure roller runs under pressure on the surface wetting roller, whereby the device performs a two-fold preliminary squeezing of the receiving material on the surface wetting roller, on the one hand, and in the squeeze roller pair, on the other hand.

9. A device as set forth in claim 8, wherein the shell of one of the rollers, comprising the surface wetting roller and the contact pressure roller (46), have profiles for introducing the liquid into the zone of contact between these two rollers, and wherein the rollers of the squeeze pair (34, 35) have substantially smooth surfaces.

10. A device as set forth in claim 8, in which all of said rollers run under contact pressure on each other, and are all within the path of movement of the receiving which urge said at least one roller towards it associated cooperating roller.

12. A device as set forth in claim 8, wherein several contact pressure rollers are arranged about a surface section of the surface wetting roller (15).

13. A device as set forth in claim 7, wherein a contact pressure mechanism associated with the surface wetting roller comprises an endless belt (87), and one of the two vessels is provided with mounting means for two guide rollers and with guide rollers mounted therein, about which guide rollers the endless belt is passed.

14. A device as set forth in claim 7, wherein one of the said vessels contains a guide element arranged at a point above the said second guide elements and extending upstream of the upper section of the surface wetting roller transversely across the path for the receiving material, formed by the second guide elements, so as to guide this material towards and to the surface wetting roller.

References Cited UNITED STATES PATENTS 3,142,241 7/1964 Limberger 89 FOREIGN PATENTS 856,846 11/1952 Germany.

300,921 9/1965 Netherlands.

NORTON ANSHER, Primary Examiner F. L. BRAUN, Assistant Examiner US. Cl. X.R. 

